Electric condenser having indicating means combined therewith



Aug. 20, 1929. 'H F, HERMAN 1,725,639

ELECTRIC CONDENSER HAVING INDICATING MEANS COMBINED THEREWITH Filed Oct. 16, 1925 [N VENTOR H Herman BY ATT RNE? Patented Aug. 20, 1929.

FFICE.

' HENRY I. HEB-HAN, OF CHAPPAQUA, NEW YORK.

ELECTRIC CONDENSER HAVING INDICATING COMlBINED THEBEWITH Application filed October 16, 1925. Serial 110. 82/3 2.

, This invention relates to variable electric condensers particularly adapted for radio receiving apparatus, although it may be used for other purposes, of the type wherein a I series of plates are mounted on and in elec-' parallel relation and equidistantl trical connection with a carrier to extend in spaced from opposite sides of the center the carrier, said plates either being fiatand of rectangular shape, or of cylindrical or curved form, and the plates of one electrode adapted to have telescoping movement in relation to the plates of the other electrode. In the construction of such condensers heretofore the plates are constructed separately from the carrier and connected thereto by mounting the same edgewise in grooves in the carrier. In an alternative form of said condensers the electrodes consist of individual cupped or flanged members and the electrode is built up by nesting the members of-the electrodes. In all of suchelectrodes due to the construction and arrangeinentof the same there is a loss of electric conductivity with a resultant loss in the efiiciency thereof in use. It is an object of the invention to overcome the above disadvantages in condensers of this character by constructing the plates inteml with a carrying base or head therefor by constructing the same from one and the same piece of material.

A further object of the invention is to combine with condensers of this character an improved indicator which is operative from the means to adjust the condenser elements to indicate the position of the condenser.-

It is a further object of the invention ,to provide an improved mounting for condensers of this character in the casing of radioreceiving apparatus in relation to a window therein through which the indices on the dial are adapted to be consecutively exposed by and in accordance with the ad'ustment of'the condenser to indicate such ad ustment. g

In the drawing accompanying and forming a part of this specification I have shown an embodiment of the'invention wherein Figure 1 is a side elevation of an electric condenser showing the same mounted in a casing of a radio receiving apparatus, only so much of the casing being shown as is essential to an understanding of the invention.

Figure 2 is a longitudinal sectional view.

Figure 3 is a cross sectional view taken on the line 3-3 of Figure 1 looking in the direction of the arrows, and

Figure 4 is a perspective view of a modified forf'lm of the electrodes shown in Figures '1 an 2.

In carrying out the embodiment of the invention shown in Figures 1 and 2 there is provided a pair of electrodes 5 and 6 of circular form, each electrode comprising a head or base-portion having integral plates? of cir- 'cular form. of substantially the same thickness and equidistantly spaced from opposite sides o f'the center of the base. The electrodesare of a one piece integral structure in that they are made from one piece or block of stock the spaced plates being formed bycuting, annular recesses into the one end of the. block. By so constructing the electrodes it has been found that there is no loss in electric conductivity and no resultant loss in efiiciency, as is the case when theplates are constructed of separate pieces of material and mounted in electrical connection with the base portion.- 1

The electrode 5 is adapted to be mounted in fixed position, shown in the present instance as mounted in the front panel 8 of dielectric material of a radio receiving casing or cabinet, said panel extending vertically upward from a base 9 and interposedbetween said baseand a shelf 10 extending forward from a closure member 11 of the casing only a portion of which is shown. To mount the electrode 5 it is'arranged with a central hub or boss 12 engaged upon one end of a sleeve 13 of insulator material in abutting relation to an annular enlargement 14 of said sleeve, and the opposite end ofthe sleeve engaging in the panel 8 with a nut 15 threaded onto the outer end to clamp the electrode carrying sleeve to the panel. V

The electrode 6 is carried by a spindle 16 mounted axially in the electrode car ng' sleeve 13 to have rotatiye movement an the mounting of the-electrode on the spindle is such" that. as the spindle is rotated movement is imparted to the electrode 6 toward or awa .from the electrode 5 according to which direction the" spindle is rotated without imparting rotative movement to either of the elec; trodes, the plates of the electrode 6 being arran ed so that they will be in opposed relation 7 to t e spacesbetween the plates of electrode 5 whereby the plates of'one electrode are adapted, to have telescoping movement with relation to the plates of the other electrode. To impart this movement to the electrode 6 the spindle has a portion having threaded connection with the electrode carrying sleeve 13, as shown at 17, whereby as the spindle is rotated, which is facilitated by a knurled button 18 at the outer end of the spindle, longitudinal movement is imparted to said spindle due to the sleeve 13 being fixed.

The electrode 6 is carried by a bushing 19 of insulator material loose on a portion of reduced diameter of the spindle extending be yond the threaded portion and confined between the threaded portion and a collar 19 fixed to the spindle, the bushing being held 1 against rotation with the spindle by pins 20 fixed at one end in the bushing and extending forward thereof in parallel relation to and at opposite sides of the threaded portion of the.

spindle and which ends are in slidable engagement with bores 21 in the electrode carrying sleeve 13. The electrode is mounted upon sa1d bushing by engaging a reducedend thereof in an opemng axially of the electrode and threading a nut on the end of said reduced portion extending through the electrode opening to clamp the electrode between said nut and the shoulder formed by the reduced portion of the bushing, as shownat 22.

. The adjustment of the condenser is indicated by a dial adapted to participate in the rotative and longitudinal movement of the spindle, said dial having spirally; arranged indices adapted to be successively exposed through an openin or window in the casing. This dial is in the orm of a cupped member or drum 23 having an axially extended tu bular portion 24 with an axial opening therein. :The drum is engaged upon the spindle to extend circumferentially around the electrode 6 in spaced relation thereto with the reduced extended portion of the spindle engaging in the opening of the extended tubular portion of the drum and mounted on the spindle by a pair of nuts threaded onto the spindle, one within said extended drum portlon and the other at the outer side, as shown at 25 in Figure 2, the nuts clamping the drum to the spindle whereby the drum will participate in the rotative and axial move-- ment of the spindle. The drum portion 23 may co-operate with the electrode 6 to serve as a plate thereof. Calibrations are arranged in spiral formation upon the periphery of the drum portion 23, in the present instance comprising numeral indices commencing and reading from a point at the open end of the drum. The periphery. of the dial drum lies contiguous to the inner surface of the shelf 10 of the casing in relation to an opening or window 26 through which to successively expose the dial indices for visual observation.

exterior of the casin as the dial is rotated and axially adjusts with the elect-rode 6 through the rotation of the spindle 16. To

facilitate the reading of the indicesthrough the window the wall of the window is arranged to converge from the outersurface'.

ure 3) in the under surface of the base of the casing is connected to the electrode 5, as at 29. The other terminal of the conductor is connected, as at 30, with a carrier 31 for a brush 32 mounted on an insulated support 33 secured to the casing base, the brush havof the dial cup extension 24, the circuit being completed by inductance through the plates ofthe condenser electrodes. To electrically.

connect the electrode 6 with the terminal 30 of the electrode a circuit closing contact or brush 34 in theform of a resilient spring finger is fixed at one end to the electrode 6 and has a rubbing contact with the interior of the dial. In operation it will be obvious that with the condenser electrodes in the position shown in Figure 2 the capacity value of'the condenser is at its minimum, and that byadjustingthe electrode 6 into interengaging relation with the electrode 5 the capacity value of the condenser is progressively increased depending upon the amount of the adjustment; i While the electrodes structed-by circularly recessing a block of material to arrange the block-with the circular and concentrically arranged plates 7, the electrodes may be of the form shown in Figure 4 wherein a blockof metal of rectangular shape is arranged with a central bore 35-for mounting the same upon the insulator sleeve 13 and then cutting parallel transverse slots 36 into one face of the block, the slots being equidistantly spaced from opposite sides of the center of the block bore to arrange the block with integral plates 37 of substantially the same thickness. In the construction of the electrode 6 the solid portion interposed between the plates 37 is cut mg a rubbing contact with the outer surface as described are con-' away to facilitate the mounting of the elec trode upon the spindle, the same as electrode 6 as shown at 22 in Figure 2.

While I have illustrated one embodiment of constructing and arranging the electrodes of the condenser whereby the electrodes may be variably adjusted relative to'the other that portions of the invention may be used without others without departing from the I scope of the invention.

come within the scope of the invention,.and

.Having thus described my "invention, '1 claim:

1. In an electric condenser, a pair ofelectrodes, each electrode comprising a head having a series of integral equidistantly spaced plates extending parallel to each other and the axis of the head, and means to mount the electrodes in axial. relation with the plates of one electrode arranged in alinement with the spaces between the plates of theother electrode, and the mounting means for the one electrode being adapted to have rotary movement and with said electrode axial movement to efi'ect'longitudinal adjust.-v

ment of the electrodes one relative to the other to position the plates of one electrode in interposed relation to the plates of the other electrode to variable extent.

2. In an electric condenser, a pair of electrodes, each electrode including a series of parallel and equidistant spaced inte ral plates, a fixed mounting for one of said e ectrodes, a spindle mounted centrally in the mounting of and insulated from the first electrbdef to have rotative movement and axial adjustment and on which the other electrode is mounted to participate in the axial movement thereof and held against rotative movement therewith, the plates of the latter electrode being arranged in lateral op,-

posed relation to and adapted to have movement into and out of the spaces-between the plates of the first electrode.

3. In an electric condenser, a pair of electrodes, each electrode including a series of parallel and equidistant spaced integral plates, a fixed mounting for one of said electrodes, a spindle mounted cent-rall in the mounting of and insulated from the rst electrode to have rotative movement and axial adjustment, means to mount the other electrode on said spindle to participate'in the axial movement thereof and held against rotative movement, and a dial to participate in the rotative and axial movement of the spindle.

4. An electric condenser asclaimed in claim 2, wherein the spindle has a threaded portion threaded into, the mounting of the one electrode, and the other electrode is mounted thereon by an insulator bushing loose on the spindle in interposed relation .to the threaded portion and a collar fi-xed bushing and electrode against rotative movement with the spindle.

6. In an electric condenser, an electrode having electrically connected plates arranged in parallel and spaced relation at opposite sides of the center thereof, a fixed insulator support for said electrode, a spindle mounted centrally in said electrode support to have rotative movement and axial adjustment, a

.s'econd electrode having electrically connected plates arranged in parallel and spaced relation at opposite sides ofthe center thereof mounted on the spindle to participate in the axial movement thereof and arranged with the plates opposed tothe spaces between the plates of the first electrode and adapted to be moved into and out of said spaces by the movement thereof with the spindle, and a cupped member mounted on the spindle to participate in the rotative and axial move ment thereof and extending around the sec-' ond electrode and having spirally arranged indices on the periphe thereof 7. In an electric con enser, a pair of electrodes each electrode including a series of integral concentrically arranged and electrically connected plates and one electrode mounted in fixed position, a spindle mounted axially of the fixed electrode mountingto have rotative and axial movement, means for mounting the other electrode on and insulating the same from the said spindle with the plates in opposed relation to the spaces between the plates of the fixedly mounted electrode and adapted to participate in the axial movementof the spindle to have adjustment longitudinally relative' -to said fixedly mounted electrode, a dial mounted on the spindle concentric to and extending around the electrode mounted on the spindle and havin indices about the circumference arranged in spiral formation and adapted to participate in .the rotative and axial movement of the spindle, and means to connect said electrodes in an electric circuit.

8. An electric condenser as claimed in claim 7 ,'wherein the dial is in the form of a drum to extend around and spaced from the electrode on the spindle with the indices arranged on the periphery thereof.

9. An electric condenser as claimed in claim 7, wherein the electrodes are connected in an electric circuit by connecting one terminal of a conductor to the fixedly mounted electrode, the other electrode being electrically connected with the dial and a brush having rubbing contact with the dial connected to the other terminal of the conductor.

10. An electric condenser as' clamied in claim 7, wherein the condenser is mounted in a casin having a window relative to which the ial is positioned to consecutively expose the indices on the dial through said window.

-11. An electric condenser. as claimed in drum to extend around and spaced fromthe electrode on the spindle with the indices arranged on the )eriphery thereof, and a casing in which t 1e condenser is mounted arranged with a window relative to which the dial is adapted to be positioned in the adjustment of the condenser to consecutively expose the dial indices through the window.

12. In an electric condenser, a pair of electrodes each electrode arranged with a series of parallelly extending and equidistantly spaced plates and the electrodes adapted to have adjustment one relative to the other to interengage the plates of one electrode with the plates of the other electrode, anda dial adapted to participate in the longitudinal adjustment of the electrodes one relative to the other and have independent rotative movement.

the plates of the other electrode, a cylindrical dial extending around. and in spaced relation to the longitudinal adjustable electrode and having indices arranged in spiral formation about the same, and means to longitudinally adjustthe one electrode relative to the other electrode and simultaneously with the adjustment of said electrode impart longitudinal and rotative adjustment to the dial.

Si ned at the city of New York, in the county of New York-and State of New York this 9th day of October, 1925.

. NRY F. HER. 

